Vitamin D Levels May Affect Blood Pressure

The health benefits of maintaining an adequate serum level of 25'hydroxy vitamin D are numerous. A recent article in the American Journal of Clinical Nutrition hypothesized that systolic blood pressure levels might be influenced by serum levels of 25-hydroxyvitamin D, or 25(OH)D.

In this cross-sectional study, data from the National Health and Nutrition Examination Survey (1988-1992) was evaluated, and the authors found a significant association between age-associated blood pressure increase and serum 25(OH)D in white subjects. Deficient subjects (<50 nmol/L, or 20 ng/ml) had an age-related systolic blood pressure (SBP) increase of 0.50 mm Hg/year, insufficient subjects (50-79 nmol/L or 20-31.6 ng/ml) 0.48 mm Hg/y, and sufficient (>80 nmol/L or 32 ng/ml) subjects had an SBP increase of 0.40 mm Hg/y. "Participants who were vitamin D deficient and insufficient had significantly higher age-associated increases in SBP than did participants who were vitamin D sufficient (p=0.01).

In this population of 7,699 people 19 yrs of age or older, 61% of whites and 92% of blacks were found to have insufficient vitamin D levels as defined as a serum 25(OH)D level less than 80 nmol/L (32 ng/ml). This was of particular concern because 65% of the black participants had vitamin D levels checked in the summer or fall, when levels are typically highest. The researchers were unable to detect a correlation between blood pressure and vitamin D in these subjects because practically all were deficient.

Judd SE, Nanes MS, Ziegler TR, et al. Optimal vitamin D status attenuates the age-associated increase in systolic blood pressure in white Americans: results from the third National Health and Nutrition Examination Survey. Am J Clin Nutr 2008;87:136-141.